Sparking plug for combustion-engines.



No. 772,856. PATENTED OCT. 18, 1904.

G. H. WISNER.

SPARKING PLUG FOR COMBUSTION ENGINES.

APPLICATION FILED JULY 24. 1902.

N0 MODEL.

WI NESSES INVENTOR K 9. a. //m

Attorneys.

Patented October 18, 1904.

UNITED STATES PATENT @EETQE.

CHARLES H. WISNER, OF FLINT, MICHIGAN, ASSIGNOR TO PETER P. G. HALL, JR.

SPARKING PLUG FOR COMBUSTION-ENGINES.

SPECIFICATION forming part of Letters Patent N0. 772,856, dated October18, 1904.

Application filed July 24, 1902. Serial No, 116,766. (No model.)

To all whom it may concern:

Be it known that 1, CHARLES H. WIsNER, a citizen of the United States,residing at Flint, county of Genesee, State of Michigan, have invented acertain new and useful Improvement in Sparking Plugs forCombustion-Engines; and I declare the following to be a full, clear, andexact description of the invention, such as will enable others skilledin the art to which it pertains to make and use the same, referencebeing had to the accompanying drawings, which form a part of thisspecification.

This invention relates to sparking plugs for explosive-engines, and hasfor its object an improved plug in which there is contained a chamberarranged to retain a portion of the burned gases, which retained portionserves as a protection to prevent the deposit on the insulating materialof carbon resulting from imperfect combustion in the chamber.

In the drawings, Figure l is a longitudinal section of the plug with thesparking electrode connected therewith. View as seen by one lookingtoward the sparking end of the electrode.

The plug A is threaded to fit a threaded opening in the cylinder B. Thehead of the plug is bored out and threaded to form a cavity 2, which islarger in diameter than abore 3, concentric with the bore of cavity 2,and the cavity 3 is extended through the stem 4 of the plug. Preferablythe base is somewhat eccentric to the body of the stem or to the truecenter of the stem 4, but accurately concentric with the bore of thecavity 2.

The cavity 2 has a seating-surface 5 above the extreme bottom of it, anda portion of the cavity concentric with the seating-surface 5 forms ashallow chamber between the insulating-disk hereinafter spoken of andthat part of the material which forms the stem 4 of the plug and formsthe web 6 between the stem L andthe walls 7, which surround the cavity2. The walls of the cavity are internally screw-threaded, and a threadednipple 8 is run into the threads in the walls of the Fig. 2 is an endcavity and holds between its inner end and the seating-surface 5 a diskof insulating material 9, preferably of sheets of mica. The disk ofinsulating material 9 is centrally perforated, and through the centralperforation extends thescrew-stem 10 of an electrode 11. A hollow piston12, fitted with a suitable binding-screw 13, is screwed onto the stem10. An electrode-point 14 is made fast to the stem 4 of the plug andarranged to be brought into proper adjustment with the extreme point 15of the electrode.

The disk 9 is round, and the body of the electrode 11 in the center ofthis disk is quite accurately adjusted along the center line of the bore3 through the stem, and the terminal 15 of the electrode is alwaysaccurately centered with respect to the bore 3, so that the electrodemay be-brought in its proper position without difficulty in assemblingthe parts.

The nipple 8 holds the insulating-disk 9 in place, and there is ashallow Wide chamber extending over the inner surface of the insu-vlating-disk at the bottom of a bottled chamher or cavity through whichthe electrode projects. The electrode itself is insulated by a broadair-space from all the metallic parts of the plug and is held withperfect insulation by means of the mica disk.

After one explosion in the engine has taken place a fresh charge isintroduced, entering the chamber as the piston is withdrawn. That partof the exploded gases which was in the cavity does not entirely leavethe cavity. The combustible fresh charge does not reach the bottom ofthe cavity, although under compression enough of the fresh charge doesextend into the cavity beyond the extreme end of the electrode 11 sothat the spark-gap is at all times in the rich combustible gases, whileacushion of burned gases lies at the bottom to prevent combustion fromextending deep enough into the cavity to coat the mica disk 9. Shouldthe first layer of mica become burned, as will sometimes happen to micaunder high heat, the plug can easily be repaired by sealing off theburned sheets and, if necessary, adding additional sheets to the rear toproduce a disk of requisite strength to resist explosion. Vhile the airin the inner end of the plug is more or less disturbed, the residualgases of the previous explosion being more or less replaced bycombustible gases, the location and shape of the shallow chamberprevents the displacement of the incombustible gases contained therein,and thus prevents the formation and deposition of soot or other matterliable to form a conductingfilm on the walls of said chamber.

The shape of the plug is such that while the part which passes into thecylinder may be made of the average size'say that of a threequarter-inchgas-pipe-the outer port may be made large to afford a large amount ofinsulating material between the electrodes and a considerable extent ofsurface.

The simplicity of the construction and the small cost incident to itsconstruction will be obvious and the ease with which it may be takenapart and put together.

What I claim is 1. Asparkingplugforcombustion-engines, provided with anoutwardly-extending passage opening into the cylinder, a second passagelarger than the first passage forming an outward extension of the same,a raised shoulder on the surface of said plug between the ends of saidpassages, said shoulder surrounding the inner end of the first-mentionedpassage at a distance therefrom, a disk made up of one or more sheets ofmica resting upon said shoulder, means for holding the mica, and anelectrode secured to said disk and extending along said passage.

2. A sparking plug for combustion-engines, provided with anoutwardly-extending passage opening into the cylinder, a second passagelarger than the first passage forming an outward extension of the same,a raised shoulder on the surface of said plug between the inner ends ofsaid passages, said shoulder surrounding the inner end of thefirst-mentioned passage at a distance therefrom, a disk of insulatingmaterial having a flat inner surface resting upon said shoulder, and anelectrode secured to said disk and extending along said passage.

3. In a sparking plug for a jump-spark system of ignition forcombustion-engines, the combination of a plug containing a chamber and acomn'iunicating passage between said chamber and the interior of theengine of smaller diameter than the chamber, an insulated electrodearranged to extend through the chamber and through the passage and toterminate near the extremity of said passage, a second electrodearranged in proximity to the first with an intervening gap,substantially as described.

4. In a sparking plug for gas-engines, the combination of a plug havinga passage through the stem thereof, a cavity in the head of said plug oflarger cross-sectional area than the stem-passage, an electrode, a diskof insulating material, means for holding the disk in position closingthe end, and spaced from the bottom of the cavity in the head of saidplug, said electrode being supported by being secured in said disk, saidelectrode being ar ranged to extend through said cavity into saidpassage and toward the inner end of the latter and a second electrodearranged in proximity to the first with an intervening gap.

5. An igniting device comprising a terminal supporting-standard, aninsulating-plate to which said standard is secured, a tubular membersurrounding said standard and a flange connected to said tubular memberand provided with a recessed portion adjacent said plate, and means forholding said insulatingplate against said flange but free of itsrecessed portion.

6. An igniting device comprising a tubular plug adapted to enter thewall of an enginecylinder and formed With an enlarged chambercommunicating with its bore exterior of such cylinder, a metal firingpin passing through such bore and into said chamber and insulatingmaterial interposed between said pin and the wall of said chamberentirely exterior of such cylinder.

7. An igniting device comprising a tubular plug adapted to enter thewall of an engine cylinder formed with an enlarged chamber communicatingwith its bore exterior of such cylinder, said chamber having an aperturein its wall and a metal firing-pin passing through said plug and spacedaway from the walls thereof, and insulating material in said apertureand surrounding said pin, said insulating material being wholly exteriorof such cylinder.

8. A sparking device for explosive-engines comprising a tubularelectrode, having bores of different diameter, a piece of insulatingmaterial across the larger bore for closing the same and arranged at adistance from the bottom thereof, and an electrode supported by saidmaterial and arranged in proximity to the inner end of the tubularelectrode.

9. Asparking plug for a combustion-engine containing a chamber, acommunicating passage between said chamber and the interior of theengine of smaller diameter than the chamber, an insulated electrodearranged to extend through the chamber and through the passage andterminating near the extremity of said passage and a second electrodearranged in proximity to the first.

LOO

10. A sparking plug for a combustion-engine comprising a chamberexterior of the engine, a communicating passage between said chamber andthe interior of the engine of smaller diameter than the chamber, aninsulated electrode arranged to extend through the chamber and throughthe passage and terminating near the extremity of said passage and asecond electrode arranged in proximity to the first. 10

In testimony whereof I sign this specifica tion in the presence of twoWitnesses.

CHARLES H. WISNER. Witnesses:

'LoTTA LEE HAYTON,

ELLIOTT J. STODDARD.

